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How Coastr works

Coastr is a marketplace for GPU time. People rent out their graphics card by the hour from a browser tab, and others rent those hours to run jobs. Five minutes is enough to read all of it.

CHAPTER 01

What is Coastr

Think of a rollercoaster. Each GPU is a ride, each hour on it is a seat, and anyone can buy a seat.

1 houris one seat: the unit you buy and sell.
0 installsEverything runs in the browser, using WebGPU.
5% feeCoastr keeps 5% of each paid hour. The seller gets 95%.

Two sides

Renters need computing power for a short time and don't want to buy a graphics card.
Sellers have a GPU that sits idle most of the day and would like it to earn something.

Coastr connects the two, holds the payment until the hour is served, and shows everything that happens in a public live feed.

CHAPTER 02

Rent a GPU

Pick a GPU that's free now, pay for the hour, send jobs. That's it.

  1. Open the “Rent a GPU” tab“Free right now” shows GPUs that are online and free for the rest of this hour, cheapest first.
  2. Tap “Rent now”Connect your wallet if you haven't yet, then confirm. The hour is yours right away.
  3. Run a jobA panel appears at the top: “Yours until HH:00”. Pick a size and tap “Run a job”. The result comes back in seconds.

Booking ahead

Under “Later today”, tap Reserve to book a future hour. When it starts, come back and tap Start to use it.

What jobs can I run? For now, one test job: the GPU computes a fractal image, which proves the hour really ran on that card. More job types are coming.
CHAPTER 03

Earn with your GPU

One button. Your GPU is tested, your hours are listed, and you earn while the tab stays open.

  1. Open “Earn with my GPU” and tap “Start earning”Coastr runs a few seconds of real AI math to measure your card's speed.
  2. Your hours go on saleThis hour and the next 7, at a suggested price. To pick other hours or another price, tap “Change hours or price” first.
  3. Keep the tab openWhen someone rents an hour, their jobs run in your tab. If you close it, your GPU shows as offline.
  4. CollectWhen a rented hour is over, tap “Collect” to receive the payment.
Requirements: a computer with a graphics card and a recent Chrome, Edge or Safari. Phones work for renting, not for earning.
CHAPTER 04

How payment works

Your money is never sent straight to a stranger. A smart contract holds it until the hour has been served.

  1. You pay, the contract holds itThe price of the hour goes into the Coastr contract on Elysium, not to the seller.
  2. The hour runsYou use the GPU during the hour you paid for.
  3. The seller collectsOnce the hour is over, the seller receives 95% and Coastr 5%.

If the GPU doesn't show up

If a seller goes offline and doesn't serve your hour, Coastr can refund you in full from the contract. The seller is then paid nothing for that hour.

A seat is a token

A reserved hour is a small token in your wallet. Until the hour starts, it can be handed to someone else. Once the hour has started, it can only be used.

CHAPTER 05

Your wallet

A wallet is your account on Coastr. It's how you pay and how you get paid.

Connecting

Tap Connect wallet at the top right. If you have a browser wallet such as MetaMask or Rabby, Coastr asks it to switch to the Elysium network. If you don't have one, Coastr creates a free test wallet in your browser so you can try straight away.

Free test funds

New wallets get a small amount of free test HYPE from Coastr, enough for a few hours of GPU. Each wallet gets it once.

Your nickname

Your address is never shown. Everyone gets a friendly nickname instead, such as “Brave Wolf”. It comes from your wallet, so it's always the same.

Testnet: Coastr runs on the Elysium testnet, Kinetiq's Hyperliquid L2. Prices are in test HYPE, which has no real value. Nothing you do here costs real money.
CHAPTER 06

Coastr GPUs

So there's always something to rent, Coastr runs a few GPUs of its own.

They're always labelled “Coastr GPU” with the Coastr logo and a Run by Coastr badge, so you never mistake them for a person. They work like any other GPU, but they're left out of the “Top earners” board, which is only for the community.

CHAPTER 07

Questions

Is it safe to let strangers use my GPU?

Jobs run inside your browser's WebGPU sandbox, the same one websites use for 3D graphics. They can't read your files or reach anything outside the tab.

Will it slow down my computer?

Only while a job is running, and jobs take seconds. To stop completely, close the tab.

What happens if I close the tab during a rented hour?

Your GPU goes offline and the renter's jobs fail. If the hour isn't served, the renter can be refunded and you don't get paid for it.

Who sets the price?

The seller. Coastr suggests a price based on your GPU's speed, and you can change it before listing.

Why do I need a wallet?

Payments go through a smart contract, which needs an address to pay you and to know who bought which hour. If you don't have a wallet, Coastr makes a test wallet for you.

What's the leaderboard?

“Top earners today” ranks sellers by what they earned today. It shows nicknames only.

Ready to ride?

Rent a GPUEarn with my GPU